Draft gear

ABSTRACT

A DRAFT GEAR HAVING OPPOSED FOLLOWERS BEING UNITARILY FORMED WITH CENTRAL WEDGING SECTIONS, EACH HAVING AT LEAST TWO INCLINED FLAT SURFACES DISPOSED IN DIVERGING RELATIONSHIP WITH RESPECT TO ONE ANOTHER. A PAIR OF ALIGNMENT RIDGES OR TRACK FORMERS ARE PROVIDED ON EACH OF HE INCLINED SURFACES SO AS TO PROVIDE A SPECIFIC FRICTION PATHWAY FOR THE MOVEMENT OF FRICTION SHOES OR WEDGE ELEMENTS THEREON. THE WEDGING SECTIONS HAVE DROPOFFS OR ARE RELIEVED AT THE ENDS THEREOF SO THAT ABUTMENT SHOULDERS WILL NOT BE FORMED DURING WEAR OF THE INCLINED SURFACES BY THE FRICTION SHOES OR ELEMENTS. THE MATERIALS USED IN CONSTRUCTING THE GEAR ARE OF HIGH QUALITY STEEL AND THE WEDGING ELEMENTS OR SHOES IN CONJUNCTION WITH THE REMAINDER OF THE COMPONENTS, HAVING WORKING OR CONTACTING ENGAGEMENTS, ARE CONTOURED SO AS TO ALLOW FOR EASY   PASSING OF THE MOVING MEMBERS, THEREBY REDUCING UNDESIRED FRICTIONAL ENGAGING CONTACTS.

United States Patent [72] Inventor Bertil E. Peterson PrimaryExaminer-Drayton E. Hoffman Chicago, Ill. Auomey --Mann, Brown. McWilliams & Bradway [2]] Appl. No. 794,926 [22] Filed Jan. 29,1969 [45]Patented Jcu fl il z h C ABSTRACT: A draft gear having opposed followersbeing [73] Ass'gnee M We estmg ompany unitarily formed with centralwedging sections, each having at least two inclined flat surfacesdisposed in diverging relation- [54) DRAFT GEAR ship with respect to oneanother. A pair of alignment ridges or track formers are provided oneach of the inclined surfaces so 6 Claims, 4 Drawing Figs.

as to provide a specific friction pathway for the movement of 1 Cl213/38 friction shoes or wedge elements thereon. The wedging seci l CI 89/10 tions have dropoffs or are relieved at the ends thereof so thatB61g/9/13 abutment shoulders will not be formed during wear of the Fled0 Search t 2 i inclined urfaces the friction shoes or elements Thematerials used in constructing the gear are of high quality steel [56]References (med and the wedging elements or shoes in conjunction withthe UNITED STATES PATENTS remainder of the components, having working orcontacting 1,374,671 4/1921 O'Connor 213/38 engagements, are contouredso as to allow for easy passing of l,409,039 3/1922 Symington.. 2l3/38the moving members, thereby reducing undesired frictional l,968.5597/1934 Kinne 2l3/38 engaging contacts.

o g 1 f; A V [/1 L V I/ 110 i I 37 I V I b av o 14 if I ml 7 //a 20a v gDRAFT GEAR BACKGROUND OF THE INVENTION The invention relates to draftgears of the friction type for railroad cars, particularly those thatare used for hauling ore and similar cargoes. The draft gear of thisinvention is particularly adapted for long wear and has a high capacityfor absorbing and dissipating energy.

DESCRIPTION OF THE PRIOR ART The prior art draft gears have employedfollowers in draft gear constructions which have been separate and apartfrom the central wedging sections and have designed the central wedgingsections, generally in the form of flat inclined surfaces, in such amanner that, during normalwear and tear, an abutment shoulder near theterminus of the inclined surface would be built up by the frictionelement or shoe riding on the inclined surface. Additionally, noprovision has been made to positively guide the friction shoe or elementin its path of travel on the wedging sections nor has provision beenmade for smooth and easy running contact of the shoe elements with theinclined-surface wedging sections.

SUMMARY OF THE INVENTION The draft gears of this invention obviate allof the aforementioned shortcomings. One embodiment of the invention isspecifically directed to a draft gear comprising a pair of opposedfollowers each having a unitarily formed central wedging section. Eachof the wedging sections have at least two inclined flat surfaces whichmay be considered as diverging in nature. A pair of guiding ridgesspaced inwardly from the edges of each of the inclined surfaces form afriction pathway over which a pair of wedge or shoe elements mounted inopposed relation are operatively supported for travel within and over amajor portion of the friction pathway. In one embodiment a recess isprovided in the inclined surface so as not to buildup wear abutments orshoulders after the gear has been in service for a relatively shortperiod of time. Spring means provided to resist the movement of thefriction elements or shoes over the inclined wedging sections of thefollowers completes the essential components of the gear.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a central plan section ofthe gear in the normal or release position with parts of the carstructure shown in plan and partly broken away;

FIG. 2 is an end view of one of the friction shoe elements depicted inFIG. 1;

FIG. 3 is a view similar to FIG. I, the gear being in the closed or buffposition; and

FIG. 4 is a perspective view of the follower and unitary central wedgingsection member depicted in FIGS. I and 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS For purposes merely ofillustration, the draft gear of this invention is depicted and will bedescribed as it specifically relates to an exemplary application andconsequently the disclosure is not to be taken as delimiting of theinvention as it is intended that the invention be measured by theappended claims.

Referring specifically to the drawing and for the purpose of showing themanner of mounting the gear 2 on a car, there is shown a pair ofdraftsills at 4 with draft lugs 6 and buffing lugs 8 attached thereto. Thebutt ofa couplet is shown at 10 and its extension shown here as a loopform or yoke at 12.

The gear 2 comprises a pair of follower and wedging members I4 and 16which are enclosed within the loop 12 and cooperate respectively withthe draft and buffing lugs 6 and 8. Each of the members 14 and 16 areprovided with a central wedging extension I8 and respectively, eachofwhich comprises a pair of diverging inclined surfaces 18a, 18b and 20aand 2012, respectively. It will be seen that the follower and wedgingmembers 14 and 16 are of unitary construction and are formed in onepiece with an integral center web section 22 and 24 of the members 14and 16 respectively for physical strength and support. It will bereadily seen that the overall design of the members 14 and 16 are suchthat there are relief sections at the end of each inclined surface suchas 14a, 14b of member 14 and 16a and 16b of member 16. The reason forthese reliefs or dropoffs will be fairly apparent as the descriptionproceeds hereinafter. Suffice to say at this point that the wedgingelements hereafter-described are designed to ride off the inclinedsurfaces at specified loads.

The inclined surfaces 18a, 18b of member 14 and 20a and 20b of member 16respectively form, in conjunction with spaced pairs of ridges 26, 27, 28and 29 of the follower members, a friction pathway or surface. Theridges and their placement are best seen in FIG. 4.

Cooperating with each of the inclined surfaces of the wedge portions 18and 20 are a pair of floating wedge elements or friction shoes 30 and 32provided with an aperture 31 and 33 respectively for support on thestraining rod 34. The friction elements or shoes 30 and 32 have inclinedsurfaces such as 30a and 32a congruent and parallel to the inclinedsurfaces of the wedge portions 18 and 20. The rounded corners 35 (seeFIG. 2) and contoured shape as at 37 of the friction elements 30 and 32provide for ease of mobility along the friction path or surface formedbetween the pairs of ridges on the inclined surfaces of the wedgeportions 18 and 20 of the followers 14 and 16 respectively.

The seat members 36 and 38 retain the friction elements 30 and 32against the inclined surfaces of the followers, which contact isobtained by springs 40 and 42 acting against end retaining seats 44 and46 held on straining rod 34 by end nut members 50 and 52.

As is well known in the art, the movement of the friction shoe elements30 and 32 on the friction surfaces or friction pathway absorbs certainimpacts and other forms of energy to buffer from these forces the car onwhich the gear is mounted. The reason for the dropoffs or reliefs 14a,14b and 16a, 16b in the follower portions 18 and 20 of followers 14 and16 respectively will be fairly apparent from a review of FIG. 3. Sincethe movement of the friction shoes will be to move over the frictionsurfaces in aligned relation, because of the pairs of ridges 26, 27, 28and 29, the controlled movement over the edge of the inclined surfacessuch as at 14a, 14b, 16a and 16b will cause any metal or materialsscraped from the inclined surfaces to drop off the outer edge orfurthest edge of the inclined surface rather than building up to ashoulder or other type of abutment that would prohibit movement of thefriction shoe along the entire path formed by the inclined surfaces.

Generally speaking the contours of the respective parts that come intoengaging contact are curved or rounded to allow ease of passing contact.For instance, the upstanding post portions 54 of follower 14 haverounded corners as at 540, likewise at 55 to cooperate with the frictionshoes for smoothpassing contacts. The design of a draft gear as shown inthe drawings obtains in addition to the attributes already noted,increased friction areas. For instance, with the herein disclosed designa 33 percent gain in friction area is obtained when the gear is in theneutral or open position. The type gear illustrated has a total frictionarea, in the neutral position, of 37.44 square inches, whereas in theclosed position it has a total frictional area of 33.00 square incheswhich latter FIG. is approximately a 69 percent gain over prior artdesigned draft gears having friction areas of 28.12 square inches in theneutral and 19.50 square inches in the closed positions. The unitarymanner of having the wedge extensions formed with the follower, thecontoured configurations of the friction shoe elements as well as thealignment ridges in the inclined friction surfaces provide forsignificant improvements in the construction and operation of draftgears.

The specific type of gear illustrated herein for purpose of disclosureis, as indicated heretofore, one of unitary cast design; of materials ofhigh-quality steel, such as a high-quality magnesium one, which isreadily cast. ldeally and preferably, the working components of the gearare quenched and tempered to obtain a Brinell hardness within the rangeof about 4 l 5-477. The gear is particularly adapted for use on ore carshaving a l75-inch pocket to accommodate the gear. At the present time.gears of the prior art design not having the features aforedescribedhave achieved eight years of wear whereas it is anticipated that thedraft gear illustrated and described herein will have at least 12 to 14years of wear because of the increased area of the wedge and shoemembers, even though the frictional capacity of the draft gear willremain essentially the same. These and other attributes of the inventionwill make themselves readily apparent to those of ordinary skill in theart.

lclaim:

l. A draft gear comprising a pair of opposed followers each having aunitarily formed central wedging section having at least two inclinedflat surfaces, 21 pair of guiding ridges spaced inwardly from the edgesof each. of said inclined surfaces thereby forming a friction pathway, apair of wedge elements mounted in opposed relation and supported fortravel over and within a major area of said friction pathway, and springmeans resisting the movement of the named parts. with a relief portionbeing provided between the follower and central wedging section tothereby permit overriding movement of said wedge elements on saidfriction pathways.

2. The draft gear in accordance with claim 1 wherein the edges of saidfollower and said friction elements are curved and contoured to allowfor smooth moving contact between each other.

3. The draft gear in accordance with claim 2 wherein the wedge elementmounted for movement on said friction pathway has a contoured andtapered forward portion for sliding engagement on said inclined flatsurfaces.

4. The draft gear in accordance with claim 3 wherein the opposedfollowers having unitarily formed central wedging sections are formed incast fashion in one procedure.

5. The draft gear in accordance with claim 4 wherein the material ofconstruction is high-manganese steel.

6. The draft gear in accordance with claim 5 in combination with an orecar having a l7 /-inch pocket to receive a draft gear and said draftgear is adapted to be received within said pocket.

